Over the past decade, great interest has been given to regulatory T (T(reg)) cells. A vast body of evidence has shown the existence and highlighted the importance of T(reg) cells in the active suppression of immune system responses. This form of immunoregulation is the dominant means utilized by the immune system to reach a harmony between reciprocal response processes in order to ensure adequate host defense with minimal host detriment. Therapeutically targeting T(reg) cells is a direct and powerful means to manipulate the immune system to achieve beneficial effects on various disease pathologies, including allergy, autoimmunity and cancer, as well as the facilitation of organ transplantation. This powerful target for immunoregulation is of much concern to practitioners and researchers of complementary and alternative medicine because it allows a great deal of control and certainty in dealing with the prevalence of debilitating immune system-related disorders for which there has been little remedy outside of Western Medicine.